Field of the Present Disclosure
The present invention relates to a method for manufacturing a flexible electrode applicable to a flexible device.
Discussion of Related Art
Conventionally, an electroless plating process of copper (Cu) has generally been used as a method of forming an electrode or wiring on a flexible polymer substrate.
As the flexible polymer substrate, a plastic substrate made of, for example, polyimide (PI), fiber reinforced plastic (FRP), polyethylene terephthalate (PET), and polyethylene naphthalate (PEN) is widely used. Although such a plastic substrate is thin and flexible, the heat resistance and the chemical stability thereof are poor. Currently, as the flexible polymer substrate material, polyimide (PI) and glass fiber reinforced plastic (FRP) have been mainly studied. However, in order to complement optical property and heat resistance, recently, polyethylene terephthalate (PET) is getting popular.
In the case of copper (Cu) electroless plating, a seed layer made of, for example, palladium (Pd), gold (Au), platinum (Pt), ruthenium (Ru), rhodium (Rh), silver (Ag), tin (Sn), etc. is formed on the polymer substrate, which, in turn, is immersed in an electroless plating bath. In this connection, the metal of the seed layer functions as a catalyst, and, thus, copper ions are reduced and precipitated on the seed layer. In this regard, since the noble metal precursor solution is used to form the seed layer, the drying process is accompanied, thereby to incur a long process time. Further, there is a limitation in forming fine line widths. In addition, there is disadvantage of using environmentally harmful chemicals.